Automatic pressure locking means



Aug. 30,1932. E. DAVIS 1,874,697

AU'IOIATIC PRESSURE LOCKING MEANS Filed June 4. 1930 '2 Sheets-Sheet '1 I NVEN TOR.

A TTORNEYS Aug. 30, 1932. E. DAVIS luyrcnuvrrc PRESSURE LOCKING umms rum June 4, 1

\\ m 5 4 6 z 4 w a 4 ,7 5 w 4 4 1- v 5 v 5 6 a a a 5 0 Z G 5 ,5 5 W a o 0 m ATTORNEYS Patented Aug. .30, 1932 UNITED STATES PATENT; OFFICE ERNEST DAVIS, 01 SYRACUSE, NEW YORK, ASSIGNOR TO THE PROSPERITY COMPANY INC., OF SYRACUSE, HEW YORK, A CORPORATION'OI NEW YORK AUTOMATIC PRESSURE LOOKING MEANS Application filed June 4, 1980. Serial 1T0. 459,220.

It has been a common practise in the pressmg machine art to provide locking means which are operated when the motor of the press reaches a predetermined position. '5 Such position is selected so that the locking means will become effective when the pressing elements. are in contact. Due to variations and adjustments of the actuating means between the motor and movable pressing element, the actual position of the movable pressing element at the time the locking means go into effect is likely to vary. An obj ect of this invention is to provide a locking means which will be operated when the pressing elements come in contact. A further object of the invention is to provide such a locking means "which will not be effected by changes in the adjustment of the toggle lever, or other actuating means, used to close the press.

A further object of the invention is to provide locking means which will be operated automatically by the pressure between the pressing elements and which will, therefore, operate at the proper time regardless of the thickness of the material in the press. Other objects and advantages of the invention will be pointed out and will become apparent as the description proceeds. The general construction of the locking I means operated by movement of the movable pressing element with respect to a member of the actuating mechanism forms the subject matter of my co-pending application Ser. No. 451,454, filed May 10, 1930;

The invention consists in the novel features and in the combinations and constructions hereinafter set forth and claimed.

. v of a pressing machine showing the manner in which my invention is applied to thepress for operation by the pressing elements.

' Figure 2 is a diagrammatic showing, partly in section, of the manual control mechanism priming machine in combination with In describing. this invention, reference is locking means in accordance with the preferred embodiment of my invention.

Figure 3 is a top plan view of a portion of the mechanism shown in Figure 2.-

Figure 4 is a fragmentary sectional view showing the resilient connection between the yoke and head of the pressing machine;

Figure5 is a section along the line 55 'of Fi ure 2.

iguie 1 shows a pressing machine of the conventional type having a head 1 movable toward and from a stationary pressin 'element or buck 2. The buck 2 is carrie on a suitable supporting bracket 3 mounted on the pressing machine frame 4:. The movable pressing element or head 1 is resiliently mounted on a yoke member 5 pivoted at 6 to an upstanding back leg 7 of the pressing machine frame. A link 8 pivoted at 9 to the ygke 5, is pivoted at its lower end at 10 to a ll crank 11 which is pivoted to the pressing machine frame at 12. The link 8 and upstanding leg of the bell crank 11 form, a

toggle.

A fluid motor 15 is pivotall mounted on 7' the pressing machine frame or oscillationabout the point 16. A piston rod 17 of the fluid motor 15, has a pivotal connection 18 with the forwardly extending arm of the bell crank 11. The fluid motor 15 is operated to rock the bell crank 11 in a clockwise direction to straighten the toggle and bring the pressing elements together to close the press. A spring 20 connected at one end to a pressing machine frame and at the other end to the forwardly extending arm of the bell crank 11 acts to rock the bell crank in a counter clockwise directionto open the press when the pressure in the fluid motor 1 5 is released. The machine thus far described, is of the conventional'type and forms no part of the present invention.

The machine is operated to bring the pressing elements together by depressing the push buttons 25, 26, shown in Figure'2. The push button 25 operates a bell crank 27 which acts against a stem 28 of an exhaust valve 29 located within a valve casing 30. A spring 31 normally holds the bellcrank '27 in position l.

nected to the such that the push button will be held up and the exhaust valve 29 free to open.

The push button 26 operates a bell crank 38 within the valve casing holds the intake valve 36 normally closed and the exhaust valve 34 normally open.

An air supply line 40 connects the intake end of the valve casing 35 and a pipe 41 connects the portion of the valve casing 35 between the valves 36, 34 with the valve casing as shown in Figure 2.

A branch pipe 42 connects, the pipe 41 with a check valve casing 43 containing a check valve 44 which is normally heldfin raised position by a spring 45.

The check valve casing 43 is connected by a pipe 46 with'the fluid motor 15.

The side of the check valve casing 43 opposite the pipe 42 is connected by a pipe 50 and branch pipe 51 with the valve casings 52 and 53. 1 5

The valve casing 53 contains an exhaust valve 54 which is normally held in closed position by a spring 5'5 and which may be opened against the compression of this spring by the operating handle 56. An exhaust port 5 is rovided through the valve casing 53, aroun the stem of the exhaust valve 54.

The valve casing 52 is similar in construction to the valve casing and contains a normally closed inlet valve 36 connected by a stem 37 to an exhaust valve 34 having a stem 33 extending through the valve casing. A sprin 38 normally holds the intake valve 36 close and the exhaust vale 34 open. The

'pipe connects with the valve'casing 52 at a point between the valves 36, 34. The intake end of the valve casing 52 is connected by a 1 pipe with the air supply pipe 40.

y The head 1 of the pressm machine is conoke' 5 by bo ts 61 which .are

. rigidly secure to the head 1 but are slidable in the yoke 5. Springs 62 surrounding the bolts 61 normally hold the head 1 spaced apart from the yoke 5 so that .the nuts 63, on

I the ends of the bolts 61, contact with the yoke 5. The yoke 5 is provided with a bearing member 65 located over a bearing block 66 formed on the head 1. When thehead and yoke are held apart by the springs 62, the bearing member 65 and bearing block-66 will be spaced apart as shown in Figures 4 and 5.

-When the pressing "elements come together as the press closes, the upward pressure from the buck 2 against the head 1 will cause the yoke 5 to compress the springs 62, and the 1 bearing member 65 will contact with the bearing block 66. Final heavy pressure is applied by the yoke 5 to the pressing head 1 through the bearing member 65 and bearing block 66.

A plunger 70 slidably mounted in the yoke member 5 contacts with a flat portion of the bearing block 66 as shown in Figures 2 and 5. A bell crank 71 pivotally mounted at 72 to an upstanding bracket on the yoke 5 is operated by the plunger 70 to actuate the valve stem 33 and through it, operate the valves in the valve casing 52.

The operation of the machine is as follows The operator closes the press by depressmg both of the push buttons 25 and 26 at the same time. This causes the exhaust valves 29 and 34 to be closed, and the intake valve 36 to be opened. Air then passes through the air supply line 40, valve casing 35, pipes 41 and 42, to the check valve casing 43. The pressure of this air will open the check valve 44 against the compression of the spring 45. The motion of the check valve 44 is very small so that when opened by air pressure from the pipe 42, the check valve-will contact with its lower seat to close the pipe 50. With the check valve 44 thus opened, air from the pipe 42 will flow through the check valve casing 43 and pipe. 46 into the fluid motor 15 to operate the fluid motor to close the press. The manual control mechanism above describedis of the conventional two-hand control type. Unless therpush button 26 is depressed, no air will be supplied from the an supply line 40, but if the push button 26 alone is depressed, the press will not, operate since the air will escape through the pipe 41 and open exhaust valve in the valve casing 30. The purpose of requiring the operation of two push buttons is to insure the safety of the operator, and require him to remove both hands from between the pressing elements before closing the press andto hold both hands on the controls during closi-ng movement. This two-hand control feature is well known in the art and forms no part of the check valve 44 will prevent back flow of air through the pipe 42. Air pressure from Y I the pipe 50 looks the fluid motor 15 so as to hold the press closed. 1

The press maybe opened by operating the handle 56 to open the exhaust valve 54 to perm it air to escape through the pipe 51. The pipe 50 below the branch pipe 51 is providedwith a throat or orifice 80 so that the escape of air through the pipe 51 will be faster than the supply of air through the pipe 50. This is necessary since the supply of air through the valve casing 52 is not cut off until the yoke 5 begins to rise to open the press.

While I have illustrated the preferred embodiment of my invention, various changes and modifications may be made therein without departing from the spirit of the appended 10 claim.- Y

What I claim is: I In a pressing machine in combination cooperative pressing elements, one of which is movable with respect to the other to open and close the press; actuating mechanism for the movable element; fluid motor means including a cylinder and piston for operating the actuating mechanism; a fluid "supply line; operator-operated three-way valve means 2, connected to the motor and controlling the operation thereof and normally in position to connect the cylinder of the motor with the outer air and operable to connect the cylinder of the motor to the fluid supply line; a second three-way valve means connected to the motor and normally in position to connect the cylinder of the motor to the outer air and operable to connect the cylinder to the fluid supply line, means whereby said second three-way valve means is operated by relative movement of the movable pressing element with respect to a member of the actuating means; and valve controlled means between v the motor and both three-wayvalve means operable:automaticallyto close the outer air connection of the cylinderthrough the second three way valve means upon operation of the first three-way valve means and operable automatically to close the outer. air connec- 'tionof the cylinder through the first threeway valve means upon operation of the second three-way valve means.

In testimony whereof, I have hereunto signed my name, at Syracuse, in the county 5 of Onondaga, and State of New York, this 24th day of May,'1930.

1 A ERNEST DAVIS, 

